Heating food and fluids in the field has always presented problems to campers and hikers. These people have only limited space and weight whigh can be devoted to their cooling needs, yet such needs are essential and may be critical if the person is subject to severe environmental conditions and has a possibility of being cut off from supplies or from support areas. These problems must be solved, yet cannot be solved using equipment which is unduly expensive or which creates problems in the field.
Heating and cooking devices for use by campers, or the like, should be easily transported in a form which does not require a great deal of space and which is not unduly heavy. Yet, at the same time, these devices should be sturdy even in severe weather and terrain conditions, as a stove or grill collapsing into a campfire can be dangerous. These requirements are made even more difficult by a further requirement that such devices can be easily and quickly assembled and disassembled in the field so that camp set-up and break-up can be efficiently and conveniently carried out by all, even those whose dexterity is impaired for some reason, such as by heavy gloves, or the like.
Cost is a further consideration for these devices. Thus, while satisfying all of the above requirements, a successful device of this type should not be difficult or costly to manufacture or be unduly expensive to the consumer. Cost is a consideration for nearly all devices in this area; however, because presently available devices do not satisfy the above-mentioned requirements while still being usable by a wide variety of people under wide variety of conditions, these known devices can be considered as being expensive. Furthermore, if there are a multiplicity of parts, or if the parts of a device are not easily replaced, or if an entirely new unit is required if one element of a unit is damaged or lost, the units are expensive.
Efficient use of fuel is another important consideration. If fuel is burned too quickly, fuel costs are high, yet if fuel is burned too slowly, cooking time is too slow. If fuel cannot be readily replenished, it becomes very important to properly ventilate the device for the most efficient fuel consumption. In conjunction with this requirement is the requirement that certain foods be kept closer to the heat source than others for efficient cooking. To be more efficient, it is desirable that such devices be amenable to use with a wide variety of cooking and heating utensils. While many known devices have a heating area large enough to hold nearly any utensil carried by a camper, such devices make inefficient use of fuel when a small utensil is heated.
Another important consideration for such equipment is adaptability for use under a variety of environmental conditions. Thus, a person may camp in maintainous terrain, in windy areas, or even on snow or ice-covered terrain such as Arctic environments. It is desirable to have one single device which can function reliably and efficiently under all of these conditions. Because military personnel are often located in remote areas which may be cut off from sources of supply, all of the above-mentioned requirements are present and elevated from mere requirements to critical needs for military personnel. Furthermore, military personnel must be highly mobile and able to make camp and break camp quickly. In addition to the above requirements, the change from canned rations to dried rations in both civilian and military areas has created new problems. In the past, a canteen cup such as used by the military could be used as a container in which to heat fluids or rations. While convenient and effective, the canteen cup still must be placed over a heat source to effect this heating.
With canned rations, certain foods, such as crackers, for example, were stored in cans. Once opened, these cans provided a convenient field stove in which a portable heat source could be placed to heat a canteen cup, or other food storage can resting on top of the can. Furthermore, food in such rations was often stored in fluid and thus could be heated or cooked in a convenient manner over such a temporary field "stove."
This system of forming field stoves worked well until the rations system in both the civilian and the military areas was converted from cans to ready-to-eat freeze dried and pouched foods. This conversion realizes many advantages over the canned food ration system but also creates several problems for the person in the field. First, the use of dried and pouched foods creates a requirement for additional water to replace the fluid heretofore present in the canned foods, such fluid being both a cooking medium and a consumable fluid. Second, the removal of the can itself eliminated the herein above-mentioned heat source containing used in conjunction with a canteen cup to form a portable field stove.
The above-described canteen cup/ration can/portable "stove" was quite satisfactory. It had the additional advantage of being cost-effective as no special equipment was needed. As no known field stove is capable of satisfying all of the above-mentioned requirements and particularly the stringent military requirement, the known devices have not found wide acceptance.
While portable stoves and grills for civilian use have been known for many years, see U.S. Pat. No. 1,096,002, and for military use, see U.S. Pat. No. 889,187, such devices are not adequate for modern use which has the above-mentioned requirements.
For example, portable grills such as those disclosed in U.S. Pat. Nos. 3,636,938; 3,975,999 and 4,186,716 all require some element such as a rock or the like, to support the grill over a heat source. As civilians and military personnel are often located in areas devoid of such supports, these grills may be nearly useless in such applications.
Devices such as that disclosed in U.S. Pat. Nos. 1,273,840 and 1,309,049 have support legs and thus overcome the just-mentioned problem. However, these devices, like the above-mentioned devices, do not protect the heat source, and therefore are not suitable for use in severe weather conditions of high winds, rain, or the like.
While portable devices such as those disclosed in U.S. Pat. Nos. 781,758; 961,975; 1,507,959 and 2,631,579 have structure for supporting the grill as well as for protecting the heat source, these devices are not durable and require many different elements to assemble and disassemble thereby making them costly, cumbersome and difficult to assemble. As such, these devices also are not entirely satisfactory for use which requires portability and durability in an easily assembled device.
U.S. Pat. Nos. 1,102,649 and 1,238,142 disclose devices which are sturdy, durable, easily transported, yet require the heat source to be placed on the ground. Still further, there is no way to vary the position of the heat source with respect to the cooking utensil for establishing efficient cooking rates or for varying the amount of ventilation to the heat source to account for wind conditions or to establish various burn rates for the heat source. While these devices may be suitable for many purposes, they are unsuitable for use on snow or ice. Furthermore, both of these devices include hinges which must be assembled during manufacture, thereby increasing the cost of the unit, and which are subject to malfunctioning in the field.
U.S. Pat. No. 3,625,195 discloses a device which supports the heat source, yet which is cumbersome to transport, may be difficult to set-up, and may not be reusable as it is intended to be disposable. While such a device is suitable for cookouts, it is not entirely satisfactory for hikers, military personnel or the like.
U.S. Pat. No. 163,202 discloses a portable cooking device which includes legs and an enclosed heat source, and therefore overcomes many of the drawbacks identified for the above-discussed devices. However, in the Houston device, the structure serving as the supporting element includes unique elements which are different from each other and also different from the structure serving as the heat source enclosure. Therefore, the Houston device is cumbersome to store and carry, and should one of these structural elements be lost, the entire device may be rendered essentially useless until that precise element or the entire unit is replaced.
None of the above devices are entirely suitable for use with a variety of different utensils. A large utensil may restrict air flow to and from the heat source via the top of the device, while a small utensil may permit too much ventilation thereby wasting heat. U.S. Pat. No. 2,965,097 discloses a device which is adjustable in size. However, the heat source used by this device rests on the ground, and thus the device suffers from the above-discussed drawbacks.